Total knee replacement systems often include a tibial implant and a femoral implant that replace the articular surfaces of the knee. Posterior-stabilized knee replacement systems can be used to replace the function of both the anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL). In some instances, posterior-stabilized knee replacement systems include varus/valgus constraint to also replace the function of the medial collateral ligament (MCL) and the lateral collateral ligament (LCL). Although a constrained knee replacement system can provide needed stability, it often introduces biomechanical inefficiencies.